This is the urban century; over half of humanity now lives in cities and more than 70 percent are expected to do so by 2050. Today, cities are hubs of social interchange, economic vitality, and innovation. Yet the pace and scale of global transformation in where and how people live pose threats...

Global trajectories for reducing carbon emissions depend on the local adoption of alternatives to conventional energy sources, technologies, and urban development. Yet, decisions on which type of capital investments to make, made by local governments as part of the normal budget cycle, typically...